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Abstract Background Development of multidrug resistance in Uropathogenic Escherichia coli (UPEC) makes treatment of Urinary Tract Infections (UTIs) a major challenge. This study was conducted to investigate the effect of trans-resveratrol (t-RSV) at a subinhibitory concentration (sub-MIC-t-RSV) on phenotypic and genotypic expression of virulence factors of clinical isolates of UPEC and develop a nanoformulation of t-RSV. Fifty-five clinical UPEC strains were investigated for the presence of virulence factors by phenotypic methods and PCR detection of virulence genes. The effect of sub-MIC-t-RSV was studied on the phenotypic and genotypic expression of virulence factors. t-RSV-loaded nanoemulgel formulation was prepared and characterized. Results Out of the 55 tested isolates, 50.9% were biofilm producers, 23.6% showed both mannose-sensitive and mannose-resistant hemagglutination, 21.8% were serum-resistant, 18.2% were hemolysin producers, while 36.4% showed cytotoxic effect on HEp-2 cells. A total of 25.5% of the isolates harbor one or more of hly-A, cnf-1 and papC genes, while 54.5% were positive for one or more of fimH, iss and BssS genes. A concentration of 100 µg/mL of t-RSV effectively downregulates the phenotypic and genotypic expression of the virulence factors in positive isolates. A stable t-RSV-nanaoemulgel with droplet size of 180.3 nm and Zetapotential of -46.9 mV was obtained. Conclusion The study proves the effective role of t-RSV as an antivirulence agent against clinical UPEC isolates in vitro and develops a stable t-RSV-nanoemulgel formulation to be assessed in vivo. The promising antibacterial and antivirulence properties of t-RSV place this natural compound to be a better alternative in the treatment of persistent UTIs.

Background: Silicosis refers to a spectrum of pulmonary diseases attributed to inhalation of free crystalline silicon dioxide. It entails inflammatory response in which Interleukin-1 alpha is a key mediator. Objectives: to evaluate the role of interleukin-1α (IL-1α) as a biochemical marker for detection of pulmonary toxic effects of silica in relation to clinical and radiological manifestations among exposed workers. Methods: The study was conducted on 64 male workers exposed to silica dust assigned to El-Harareyat Factory of Alexandria. An interviewing questionnaire was used to collect data about personal, occupational and medical characteristics. Pulmonary function testing, plain chest radiographs and laboratory assessment of serum level of IL-1α were done for all workers. IL-1α was assessed also among a matched control group. Results: Prevalence of silicosis was 37.5%. Serum IL-1α level among silica-exposed workers was 2.8±1.8 pg/ml while it was undetected among a control group of healthy males. IL-1α was positively correlated with wheezes, negatively correlated with FVC, FEV1, MMEF, FEF50%, positively correlated with extent of nodular opacities in lung zones and presence of enlarged and calcified hilar lymph nodes. Conclusion: IL-1α can be a good monitoring marker for the earliest sign of silicosis; hilar lymphadenopathy.